[Concepts] Type Constraints

Add support for type-constraints in template type parameters.
Also add support for template type parameters as pack expansions (where the type constraint can now contain an unexpanded parameter pack).

Differential Revision: https://reviews.llvm.org/D44352

1 files changed, 10 insertions, 1 deletions

diff --git a/clang/lib/AST/TextNodeDumper.cpp b/clang/lib/AST/TextNodeDumper.cpp
index fa7f4130b76..965ad17fcfa 100644
--- a/clang/lib/AST/TextNodeDumper.cpp
+++ b/clang/lib/AST/TextNodeDumper.cpp
@@ -1694,7 +1694,16 @@ void TextNodeDumper::VisitBuiltinTemplateDecl(const BuiltinTemplateDecl *D) {
 }
 
 void TextNodeDumper::VisitTemplateTypeParmDecl(const TemplateTypeParmDecl *D) {
-  if (D->wasDeclaredWithTypename())
+  if (const auto *TC = D->getTypeConstraint()) {
+    OS << " ";
+    dumpBareDeclRef(TC->getNamedConcept());
+    if (TC->getNamedConcept() != TC->getFoundDecl()) {
+      OS << " (";
+      dumpBareDeclRef(TC->getFoundDecl());
+      OS << ")";
+    }
+    Visit(TC->getImmediatelyDeclaredConstraint());
+  } else if (D->wasDeclaredWithTypename())
     OS << " typename";
   else
     OS << " class";